Review: Apple vs Google USB-C Headphone Adapters

[minimalist]

How do you deal with clock synchronization issues between channels handled by different dongles? Channels have to be precisely time-aligned, which seems difficult to do if they are separate USB devices.

lsusb gives strong hints that the dongle runs in synchronized mode (on an internal clock synchronized to USB SOF packages). That should avoid any sync issues:

...
AudioControl Interface Descriptor:
bLength 8
bDescriptorType 36
bDescriptorSubtype 10 (CLOCK_SOURCE)
bClockID 9
bmAttributes 7 Internal programmable clock (synchronized to SOF)

...

Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 13
Transfer Type Isochronous
Synch Type Synchronous
Usage Type Data
wMaxPacketSize 0x0120 1x 288 bytes
bInterval 1
...